Weighing the Risks of Mass Vaccinations

Weighing the Risks of Mass Vaccinations

Like most 14-year-old girls, Natalie Morton probably didn’t spend too much
time worrying about cervical cancer. But along with all of her female
classmates at the Blue Coat Church of England school in Coventry, she
received a vaccine on Sept. 28 designed to protect her from the disease.
Within a few hours, she was dead.

Amid the ensuing media bonanza, local health officials immediately announced
a “full and urgent” investigation into Morton’s death and ordered a batch of
the vaccine to be withheld as a precaution. Less than a day later, a
preliminary post-mortem examination found that the vaccine was unlikely to
have killed Morton, blaming instead a “serious underlying medical
condition.” Still, as many Western nations are about to begin massive
inoculation programs against the H1N1 influenza, Morton’s death underlines
the cruel reality behind any vaccination campaign: there’s always the risk
that a small number of vaccine recipients will suffer an adverse
reaction — and that it sometimes can be deadly.

“You can never ensure a vaccine is completely safe,” says Hugh Pennington,
an emeritus professor of virology at the University of Aberdeen in Scotland.
“Clinical trials are on the magnitude of thousands and can screen out common
and mild reactions for the vaccine — fever and sore arms mostly. But if a
vaccine causes a severe reaction in one in a million people, there’s no way
to test for that.”

Morton died after receiving GlaxoSmithKleine’s Cervarix, one of two vaccines
designed to protect women from the human papilloma virus , a sexually
transmitted infection linked to most cervical cancers. Introduced last
year, Cervarix is expected to cut deaths from cervical cancer in Britain by
about 75% — or around 650 deaths a year. So far, the vaccine has been
given to 1.4 million women in Britain, and Morton’s death is the first to be
possibly linked to the shot. But there have also been less serious side effects in
recipients. Britain’s Medicines and Healthcare Products Regulatory Agency
has recorded more than 2,000 suspected reactions to the vaccine since April
2008, although the most common reports of soreness, fainting and nausea may
be a result of the act of injection rather than the drug itself.

Given the risks, the decision to launch a mass vaccination program can be
fraught. According to Jacob Weisberg’s book The Bush Tragedy, President
George W. Bush and Vice President Dick Cheney were split in 2002 over
whether to administer a nationwide smallpox vaccination program in the U.S.
Cheney argued that doing so would be a prudent counterterrorism step. Bush
overruled him because the program could have resulted in dozens of deaths.
Health officials don’t always get
the decision right. In March 1976, the U.S. government ordered a mass
vaccination program against a swine flu virus they feared would cause a
pandemic. Within weeks, reports surfaced of people developing Guillain-Barrsyndrome, a paralyzing nerve disease that can be caused by the vaccine. More
than 30 people eventually died of the condition. Facing protests, federal
officials abruptly canceled the program in December.

But decisively linking deaths to a vaccine can be difficult, Pennington
says, pointing out that there is still debate among experts as to how many
of the 1976 Guillain-Barr deaths were actually caused by the vaccine. For this
reason, health officials fear that adverse reactions in vaccine
recipients can make the already-difficult job of convincing
healthy people to receive inoculations even more challenging. For whatever
reason, people tend to fear vaccines more than other medicines. This has
been the case since the first vaccinations were given to prevent a spread of
smallpox in England in the late 18th century. That vaccine used bovine
ingredients and
people feared the injections would turn them into cows.

“The oft-cited example is concern over an autism link with the [measles,
mumps and rubella] vaccine,” Pennington says. “In America, high uptake of
the vaccine led to the eradication of measles. But in Europe, enough parents
refused to let their children have the vaccine that it gave the virus a home
to circulate and continue to infect people.”

As there is currently not enough H1N1 vaccine to inoculate all Americans,
officials are worried that front-line health-workers, who should be among
the first in line for the injections, might refuse over safety concerns.
That could compromise health workers’ ability to treat patients who are
hospitalized with the disease. A study of 11 focus groups conducted in
Canada prior to the H1N1 outbreak found that health-care workers might
refuse to immunize their children and themselves if they believed the risks
of a new vaccine outweigh the benefits, according to a report in The
Emergency Health Threats Journal in August. Another study published last
month in the online edition of the British Medical Journal found that less
than half of Hong Kong health care workers said they intended to
receive a H1N1 influenza vaccine.

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